The amount of times that you perform an exercise. For instance, pretend that you are performing a bench press. You pick up the bar, you lower it, pause and lift it up. That action of executing the movement for one time counts for 1 repetition. If you perform that same movement a second time, then that is your second repetition, and so on.

The number of efforts in a set.

Number of times a particular movement is performed.

the number of times an exercise is done in a row. Each set is made up of a certain number of reps.

Doing an exercise one time.

in relation to weight training or interval training, the number of times that an exercise is done.